In the calculus of functions of a single variable, we used our knowledge of lines to study curves in the plane. We investigated tangents and found that, when highly magnified, differentiable curves were effectively linear. To study the calculus of functions of more than one variable in the next chapter, we start with planes and use our knowledge of planes to study the surfaces that are the grap...

If you are traveling along a space curve, the Cartesian i, j, and k coordinate system for representing the vectors describing your motion are not truly relevant to you. What is meaningful instead are the vectors representative of your forward direction (the unit tangent vector T), the direction in which your path is turning (the unit normal vector N), and the tendency of your motion to “twist” ...

ESP students are usually suggested to master general and academic word lists such as Wests’ (1953) General Service List (GSL) and Coxhead’s (2000) Academic Word List (AWL) to be able to read their academic texts. However, it seems that university students may not need to learn all the words in the two lists as some words in the lists are of less frequency in academic texts. Moreover, there are ...

This paper investigates stylistic changes in a set of Portuguese historical texts ranging from the 17 to the early 20 century and presents a supervised method to classify them per century. Four stylistic features – average sentence length (ASL), average word length (AWL), lexical density (LD), and lexical richness (LR) – were automatically extracted for each sub-corpus. The initial analysis of ...

BACKGROUND Obstructive sleep apnea is strongly associated with obesity, particularly abdominal obesity common in centrally obese males. Previous studies have demonstrated that intra-abdominal pressure (IAP) is increased in morbid obesity, and tracheal traction forces may influence pharyngeal airway collapsibility. This study aimed to investigate that whether IAP plays a role in the mechanism of...

Bactrocera cucurbitae (Coquillett), also known as melon fruit fly, is one of the major insect pests of cucurbits in several parts of Asia, Africa and Pacific. In the present investigation, effect of lectins from two sources i.e. Arisaema intermedium Blume and Arisaema wallichianum Hook f. (Family-Araceae) has been studied on the development of second instar larvae of melon fruit fly. The lectin...

AIM To evaluate the safety and feasibility of a new technology combining low-pressure pneumoperitoneum (LPP) and abdominal wall lift (AWL) in laparoscopic total mesorectal excision (TME) for rectal cancer. METHODS From November 2015 to July 2017, 26 patients underwent laparoscopic TME for rectal cancer using LPP (6-8 mmHg) with subcutaneous AWL in Qilu Hospital of Shandong University, Jinan, ...

The Cestrophorini are small katydids of Ecuador’s montane rainforest bearing a prominent awl-shaped fastigium verticis. They unusual among Conocephalinae in lacking pre-tympanic ear chambers: their eardrums exposed on fore tibiae. There presently two genera, Cestrophorus Redtenbacher, 1891 and Acanthacara Scudder, 1869. Awl-head habitat includes both climax forest anthropogenically disturbed ar...

The dermal papilla comprises the specialised mesenchymal cells at the base of the hair follicle. Communication between dermal papilla cells and the overlying epithelium is essential for differentiation of the hair follicle lineages. We report that Sox2 is expressed in all dermal papillae at E16.5, but from E18.5 onwards expression is confined to a subset of dermal papillae. In postnatal skin, S...

This article concerns a corpus-based lexical study that is aimed at teaching academic vocabulary to address the specific needs of Chinese undergraduates majoring in information engineering. A 1,024,882-word corpus of Information Engineering English Corpus (IEEC) was built on the basis of university-level textbook materials drawn from ten compulsory courses for information engineering students. ...