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Sensory neurons embedded in skin are responsible for the sense of touch. In humans and other mammals, touch sensation depends on thousands of diverse somatosensory neurons. By contrast, Caenorhabditis elegans nematodes have six gentle touch receptor neurons linked to simple behaviors. The classical touch assay uses an eyebrow hair to stimulate freely moving C. elegans, evoking evasive behavioral responses. This assay has led to the discovery of genes required for touch sensation, but does not provide control over stimulus strength or position. Here, we present an integrated system for performing automated, quantitative touch assays that circumvents these limitations and incorporates automated measurements of behavioral responses. The Highly Automated Worm Kicker (HAWK) unites a microfabricated silicon force sensor holding a glass bead forming the contact surface and video analysis with real-time force and position control. Using this system, we stimulated animals along the anterior-posterior axis and compared responses in wild-type and spc-1(dn) transgenic animals, which have a touch defect due to expression of a dominant-negative α-spectrin protein fragment. As expected from prior studies, delivering large stimuli anterior and posterior to the mid-point of the body evoked a reversal and a speed-up, respectively. The probability of evoking a response of either kind depended on stimulus strength and location; once initiated, the magnitude and quality of both reversal and speed-up behavioral responses were uncorrelated with stimulus location, strength, or the absence or presence of the spc-1(dn) transgene. Wild-type animals failed to respond when the stimulus was applied near the mid-point. These results show that stimulus strength and location govern the activation of a characteristic motor program and that the C. elegans body surface consists of two receptive fields separated by a gap.

Influence of corrugation of limited extent on the performance of fixed-incline slider bearings of infinite width is investigated numerically. Effects of the corrugated section's parameters like its location, length, and corrugation amplitude, on pressure distribution in the hearing's fluid film, its load supporting capacity W and flow rate, are considered. When this section is near the entrance to the bearing gap, pressure and W are reduced in comparison with the smooth wall case. As this section is located further downstream, peak pressure and W increase, whereas flow rate decreases. These effects are reinforced by longer corrugated section and larger corrugation amplitude. The results thus point to a simple way to substantially enhance a bearing's load-supporting capacity.

The demand for dietary fiber-rich cookies has increased due to customer awareness about the importance of dietary fiber in human health. In addition, the urge of creating food sustainability has led to the need to reuse food by-products. In this study, dietary fiber-rich cookies were developed by incorporating jackfruit rind (JFR) powder, a by-product of jackfruit processing, as a replacement for wheat flour. The study aimed to evaluate the effects of different replacement levels (0, 10, 20, 30 and 40 %) on the proximate composition, physical properties and overall sensory acceptability of the cookies. While JFR powder addition led to a significant increase in dietary fiber and antioxidant (phenolics, flavonoids and carotenoids) contents of the cookies, the physical properties and overall acceptability of the cookies were adversely affected. The total dietary fiber and total phenolic content of the cookies at 40 % JFR powder addition were 5 and 5.5 times as much as those of the cookies with 0 % JFR powder addition. To address the adverse effects of JFR addition, various concentrations of ascorbic acid (AA), a dough improver agent, were added to the blended dough, and their effects on dough and cookie properties were investigated. With the addition of ascorbic acid at concentrations of 200 mg ascorbic acid per 100 g of the blend flour, the cookie density and cookie hardness reduced by 16 % and 31 %, respectively while the overall acceptability increased by 37 % compared to those of the cookies without ascorbic acid addition.

Trong bài báo này, nhóm tác giả đề xuất sử dụng nền tảng phần mềm hỗ trợ làm việc với máy tính lượng tử Qiskit để nghiên cứu các thuật toán lượng tử sau khi đối sánh các đặc tính của bốn nền tảng phổ biến là Forest, ProjectQ, QDK và Qiskit. Cùng với đó, nhóm tác giả khai triển hợp số N = 15 thành các thừa số bằng thuật toán lượng tử Shor và chạy chúng trên máy tính lượng tử IBM thông qua cloud của nền tảng Qiskit. Kết quả cho thấy, với một bài toán gần như được xem là bất khả thi đối với thuật toán cổ điển lại có thể dễ dàng được giải bằng thuật toán lượng tử nhờ các tính chất lượng tử thông qua việc chỉ ra các tính chất và “hành xử” của vật lí lượng tử trong từng bước của thuật toán.

In recent years, essential oils extracted from different plant species have become increasingly popular in the production of pharmaceuticals, cosmetics, and foods. The essential oil from orange (Citrus sinensis) is important in large-scale applications due to its antibacterial, antioxidant activities, and pleasant aroma. In this study, factors affecting the production of orange essential oil on a distillation device with an operating capacity of 50 L/batch, including the ratio of material to water, temperature, and time distillation, have been surveyed. Through the survey, it was found that the raw materials were pureed, the materials: water ratio was 1:3 g/g, the water heating temperature was 130 °C, and the distillation time was 140 min. The yield of the essential oil was 1.8 mL/g with compounds limonene accounting for 98%, α-Pinene (0.655–0.734%), and β-Pinene (1.114 and 1.163%) by the GC-MS method. The review also found that the hydrodistillation equipment was designed to be suitable for the semi-industrial scales of orange essential oil due to its stable yield and volatile compounds contained in the essential oil.