Dispersion Size-Consistency

A multivariate adiabatic connection (MAC) framework for describing dispersion interactions in a system consisting of non-overlapping monomers is presented. By constraining the density to the physical ground-state density of the supersystem, the MAC enables a rigorous separation of induction and dispersion effects. The exact dispersion energy is obtained from the zero-temperature fluctuation-dissipation theorem and partitioned into increments corresponding to the interaction energy gained when an additional monomer is added to a -monomer system. The total dispersion energy of an -monomer system is independent of any partitioning into subsystems. This statement of dispersion size consistency is shown to be an exact constraint. The resulting additive separability of the dispersion energy results from multiplicative separability of the generalized screening factor defined as the inverse generalized dielectric function. Many-body perturbation theory (MBPT) is found to violate dispersion size-consistency because perturbative approximations to the generalized screening factor are nonseparable; on the other hand, random phase approximation-type methods produce separable generalized screening factors and therefore preserve dispersion size-consistency. This result further explains the previously observed increase in relative errors of MBPT for dispersion interactions as the system size increases. Implications for electronic structure theory and applications to supramolecular materials and condensed matter are discussed.

Application of the six sigma DMAIC in quality control of potato chips to reduce production defects

To produce competitive products, Small Medium Enterprises (SMEs), one of which is Agronas as a potato chip producer in Batu City, must continue to improve the quality of their products by minimizing production defects. Quality defects on potato chips occurred in color, crispness, wholeness, and size consistency indicators. This study aimed to identify and analyze the factors causing defects in potato chips and to design alternative improvement strategies. The research method used is Six Sigma Define, Measure, Analyze, Improve dan Control (DMAIC), with a sample size of 15 packs for each variable. The results showed that the main priority of the defined stage for quality improvement was crispness and size consistency with a Critical To Quality (CTQ) value of 80.2%. In the measuring stage, based on the process capability value, the final result is 82.3% which has a value above the industry standard in Indonesia of 69.2%. The result of the analysis of the DPMO value of 177,425 is equivalent to 2.43 sigma. The priority of improvement is the two highest defect levels of crispness and size consistency. Factors causing defects in potato chip crispness include limited manpower, lack of supervision and training, different levels of quality, manual packaging, and less than optimal frying. Alternative improvement strategies are labor controlling from the manager, providing training and process SOPs, supervising the selection of raw materials, and checking packaging equipment regularly. Factors causing defects in potato chips’ size consistency include limited manpower, lack of supervision and training, and the absence of a chip rating machine. Alternative improvements include training and process SOPs, supervision in grading chips, and procurement of grading machines.

Endoscopic and Endoscopically-Assisted Resection of Intraventricular Lesions Using a Neuroendoscopic Ultrasonic Aspirator

The development of minimally invasive neuroendoscopy has advanced in recent years. The introduction of the neuroendoscopic ultrasonic aspirator (NUA) broadened the treatment spectrum of neuroendoscopy. We aim to describe our experience with the use of NUA for the resection of intraventricular lesions. Here, we present consecutive retrospective case series of adult and pediatric patients undergoing resection of an intraventricular lesion with a NUA (Endoscopic Neurosurgical Pen, Söring GmbH, Quickborn, Germany) between January 2019 and April 2020. Eight patients between the age of 0.5 and 73 years underwent surgery using NUA and were included in this study. In four patients, an endoscopic assisted (EA) resection of the lesion was undertaken, while in four patients, the lesion was removed using purely endoscopic (PE) resection. In all cases, gross/near total resection was achieved. The average blood loss was 142.5 ± 90.4 mL (range 50–300 mL). Transient morbidity was seen in four patients (50%), while permanent morbidity or mortality did not occur. The NUA seems to be a safe and valuable tool for the minimally invasive resection of intraventricular lesions in selected cases. The type, size, consistency, and vascularization of the lesion limit at times the purely endoscopic use of the NUA.

Dental biofilm-induced gingivitis in children and adolescents. A literature review

Dental biofilm-induced gingivitis is extremely common in children and adolescents and it affects the majority of children over 7 years old. It is characterised by inflammation, consisting in changes of colour, size, consistency and texture. Although most of the times gingivitis does not progress into periodontitis, it is important to diagnose and properly treat this disease, as gingivitis precedes periodontitis. The present paper aims to review the main findings of microbial etiology and epidemiology of dental biofilm-induced gingivitis mediated by local risk factors, as well as the role of oral hygiene in preventing bacterial colonization.

Neck lumps

Whilst dental healthcare professionals naturally focus on assessment of the teeth and the supporting tissues, they also have an important role in assessing the whole oro-facial complex and the neck. Assessment of the neck is particularly important, not least, because it contains the regional lymph nodes that are involved in immune surveillance of the head and neck region. The neck also contains the major salivary glands: the sub­mandibular gland and the tail of the parotid gland. Mid-line structures include the hyoid bone, larynx, and trachea, along with the thyroid gland and parathyroid glands. The assessment of these anatomical structures should form part of the routine clinical examination. The dis­covery of an abnormality in the neck, which may not have been noticed by the patient, may expedite the diagnosis of significant disease and facilitate a timely intervention. A through understanding of the anatomy of the neck is essential and informs the clinical examination. It is also important to understand the concept of the anatomical levels that map out the lymph node groups of the neck (Chapter 1; Fig. 1.2). Accurate assessment of the neck is usually best achieved by a combination of visual inspection and palpation, with the patient in a slightly reclined position, the clinician standing behind the patient. Any lumps, e.g. enlarged lymph nodes, are described by anatomical site, size, consistency (cystic, soft, rubbery, hard), whether the lump is mobile or fixed to the underlying tissue, and if palpation elic­its pain or discomfort. The combination of these parameters will help to formulate the differential diagnosis; for example, an isolated hard lump that is fixed to underlying structures is likely to represent meta­static cancer, whereas, bilateral soft lumps that are mobile and painful to palpation are likely to represent lymphadenitis as a consequence of systemic infection. Ultrasound examination can be used to ascertain important informa­tion about a neck lump such as the site (precise anatomical location, superficial or deep), size, consistency (solid or cystic), and multi-focality. Doppler settings can help to establish the vascularity of a lesion and its proximity to major vessels.

Improvement of Performance, Stability, and Continuity by Modified Size-Consistent Multipartitioning QM/MM Method

For condensed systems, the incorporation of quantum chemical solvent effects into molecular dynamics simulations has been a major concern. To this end, quantum mechanical/molecular mechanical (QM/MM) techniques are popular and powerful options to treat gigantic systems. However, they cannot be directly applied because of temporal and spatial discontinuity problems. To overcome these problems, in a previous study, we proposed a corrective QM/MM method, size-consistent multipartitioning (SCMP) QM/MM, and successfully demonstrated that, using SCMP, it is possible to perform stable molecular dynamics simulations by effectively taking into account solvent quantum chemical effects. The SCMP method is characterized by two original features: size-consistency of a QM region among all QM/MM partitioning and partitioning update. However, in our previous study, the performance was not fully elicited compared to the theoretical upper bound, and the optimal partitioning update protocol and parameters were not fully verified. To elicit the potential performance, in the present study, we simplified the theoretical framework and modified the partitioning protocol.