Reliability Parameter Interval Estimation of NC Machine Tools considering Working Conditions

Aiming at the problem that the parameter interval estimation of NC machine tool’s reliability model considering working conditions established by Hongzhou is difficult to implement, given that it has several independent variables, an improved interval estimation method based on Bootstrap is proposed. Firstly, the two-step estimation method was used to calculate the point estimation of NC machine tool’s reliability parameter in test field, based on which B resamplings are generated based on the point estimation. The reliability parameter’s point estimation of the resamplings was obtained by maximum likelihood estimation. Permutation of B point estimations was made in ascending order and the interval estimations were obtained by the α quantile of the permutation. Case study indicated that the location and length of the interval estimation of NC machine tools’ reliability parameter, under different levels of working condition covariates, vary obviously

Understanding the Role of Streamer Emotion in E-Commerce Livestreaming

The combination of e-commerce and livestreaming video (e-commerce livestreaming) offers an unprecedented opportunity for streamers (salespeople) to show their emotional displays to viewers (consumers) in real-time. However, it remains unclear how and to what extent streamer emotion influences purchase intentions, especially in the context of different product types where consumers have different decision-making considerations. Based on the stereotype content model, which considers two basic dimensions of social judgments (i.e., warmth and competence), this study intends to explore the impact of the interaction effect of streamer emotion (happiness vs. neutrality) and product type (utilitarian vs. hedonic product) on consumers’ purchase intentions and behaviors. Both laboratory experiment and secondary data analysis will be conducted to test our hypotheses. We hope this study can not only extend the livestreaming and emotion-related literature but also provide suggestions on emotional expressions for streamers in their marketing campaigns

Prepoznavanje građevina pogođenih potresom temeljem korelacijske detekcije promjena obilježja teksture na SAR snimkama

The detection of building damage due to earthquakes is crucial for disaster management and disaster relief activities. Change detection methodologies using satellite images, such as synthetic aperture radar (SAR) data, have being applied in earthquake damage detection. Information contained within SAR data relating to earthquake damage of buildings can be disturbed easily by other factors. This paper presents a multitemporal change detection approach intended to identify and evaluate information pertaining to earthquake damage by fully exploiting the abundant texture features of SAR imagery. The approach is based on two images, which are constructed through principal components of multiple texture features. An independent principal components analysis technique is used to extract multiple texture feature components. Then, correlation analysis is performed to detect the distribution information of earthquake-damaged buildings. The performance of the technique was evaluated in the town of Jiegu (affected by the 2010 Yushu earthquake) and in the Kathmandu Valley (struck by the 2015 Nepal earthquake) for which the overall accuracy of building detection was 87.8% and 84.6%, respectively. Cross-validation results showed the proposed approach is more sensitive than existing methods to the detection of damaged buildings. Overall, the method is an effective damage detection approach that could support post-earthquake management activities in future events.Detekcija oštećenja građevina uzrokovanih potresom od presudne je važnosti za upravljanje rizicima od katastrofa i aktivnostima prilikom elementarnih nepogoda. Metodologije detekcije promjena, koristeći satelitske snimke kao što su podaci radara sa sintetičkim otvorom antene (SAR), korištene su u detekciji oštećenja od potresa. Informacije sadržane unutar SAR podataka, koje se odnose na oštećenja građevina uzrokovana potresom, mogu lako sadržavati šumove zbog drugih faktora. Ovaj rad prikazuje viševremenski pristup detekciji promjena kako bi se identificirale i procijenile informacije koje se odnose na oštećenja od potresa koristeći u potpunosti značajke teksture SAR snimaka. Pristup se temelji na dvije snimke koje su izrađene kroz glavne komponente višestrukih osobina tekstura. Neovisna analiza glavnih komponenti koristi se kako bi se izdvojile komponente višestrukih tekstura. Nakon toga provodi se korelacijska analiza kako bi se detektirale informacije o distribuciji građevina oštećenih potresom. Učinkovitost ove tehnike ispitana je u gradu Jiegu (kojega je 2010. godine pogodio potres Yushu) te u dolini Kathmandu (koju je 2015. godine pogodio potres Nepal), u kojoj je ukupna točnost detektiranja građevina bila 87,8%, odnosno 84,6%. Rezultati međusobne provjere valjanosti pokazali su da je predloženi pristup osjetljiviji od postojećih metoda za detektiranje oštećenih građevina. Općenito govoreći, metoda je učinkovit pristup detektiranja oštećenja koji može u budućnosti pružati potporu u aktivnostima upravljanja nakon potresa

Rural Livelihood And Poverty In Tanzania: A case study of Mkinga District, Tanga Region

This paper aims to examine rural livelihood and poverty in Tanzania within communities at Mkinga district, Tanga region. Livelihood diversification is not well understood and adopted as a coping strategy due to various risk, shocks and uncertainties in the study area. To alleviate poverty, government should promote livelihood diversifications together with associated variables that influence access to livelihood assets. Establishment of adaptation measures, inland aquaculture, tourism and other income generation activities can subsidize their struggle for survival. It should be noted that in rural areas development of agriculture sector plays a vital role. However, the efforts of the government and other stakeholders in rural development should put the same efforts on non farming activities such as adaptation measures on climate change, rural insurance, rural finance, extension services to fishers and favorable business environment. Key words: Livelihood, livelihood framework, Assets

Functional Characterization of Homo- and Heteromeric Channel Kinases TRPM6 and TRPM7

TRPM6 and TRPM7 are two known channel kinases that play important roles in various physiological processes, including Mg2+ homeostasis. Mutations in TRPM6 cause hereditary hypomagnesemia and secondary hypocalcemia (HSH). However, whether TRPM6 encodes functional channels is controversial. Here we demonstrate several signature features of TRPM6 that distinguish TRPM6 from TRPM7 and TRPM6/7 channels. We show that heterologous expression of TRPM6 but not the mutant TRPM6S141L produces functional channels with divalent cation permeability profile and pH sensitivity distinctive from those of TRPM7 channels and TRPM6/7 complexes. TRPM6 exhibits unique unitary conductance that is 2- and 1.5-fold bigger than that of TRPM7 and TRPM6/7. Moreover, micromolar levels of 2-aminoethoxydiphenyl borate (2-APB) maximally increase TRPM6 but significantly inhibit TRPM7 channel activities; whereas millimolar concentrations of 2-APB potentiate TRPM6/7 and TRPM7 channel activities. Furthermore, Mg2+ and Ca2+ entry through TRPM6 is enhanced three- to fourfold by 2-APB. Collectively, these results indicate that TRPM6 forms functional homomeric channels as well as heteromeric TRPM6/7 complexes. The unique characteristics of these three channel types, TRPM6, TRPM7, and TRPM6/7, suggest that they may play different roles in vivo

Prediction of complex super-secondary structure βαβ motifs based on combined features

AbstractPrediction of a complex super-secondary structure is a key step in the study of tertiary structures of proteins. The strand-loop-helix-loop-strand (βαβ) motif is an important complex super-secondary structure in proteins. Many functional sites and active sites often occur in polypeptides of βαβ motifs. Therefore, the accurate prediction of βαβ motifs is very important to recognizing protein tertiary structure and the study of protein function. In this study, the βαβ motif dataset was first constructed using the DSSP package. A statistical analysis was then performed on βαβ motifs and non-βαβ motifs. The target motif was selected, and the length of the loop-α-loop varies from 10 to 26 amino acids. The ideal fixed-length pattern comprised 32 amino acids. A Support Vector Machine algorithm was developed for predicting βαβ motifs by using the sequence information, the predicted structure and function information to express the sequence feature. The overall predictive accuracy of 5-fold cross-validation and independent test was 81.7% and 76.7%, respectively. The Matthew’s correlation coefficient of the 5-fold cross-validation and independent test are 0.63 and 0.53, respectively. Results demonstrate that the proposed method is an effective approach for predicting βαβ motifs and can be used for structure and function studies of proteins

Potentiation of TRPM7 Inward Currents by Protons

TRPM7 is unique in being both an ion channel and a protein kinase. It conducts a large outward current at +100 mV but a small inward current at voltages ranging from −100 to −40 mV under physiological ionic conditions. Here we show that the small inward current of TRPM7 was dramatically enhanced by a decrease in extracellular pH, with an ∼10-fold increase at pH 4.0 and 1–2-fold increase at pH 6.0. Several lines of evidence suggest that protons enhance TRPM7 inward currents by competing with Ca2+ and Mg2+ for binding sites, thereby releasing blockade of divalent cations on inward monovalent currents. First, extracellular protons significantly increased monovalent cation permeability. Second, higher proton concentrations were required to induce 50% of maximal increase in TRPM7 currents when the external Ca2+ and Mg2+ concentrations were increased. Third, the apparent affinity for Ca2+ and Mg2+ was significantly diminished at elevated external H+ concentrations. Fourth, the anomalous-mole fraction behavior of H+ permeation further suggests that protons compete with divalent cations for binding sites in the TRPM7 pore. Taken together, it appears that at physiological pH (7.4), Ca2+ and Mg2+ bind to TRPM7 and inhibit the monovalent cationic currents; whereas at high H+ concentrations, the affinity of TRPM7 for Ca2+ and Mg2+ is decreased, thereby allowing monovalent cations to pass through TRPM7. Furthermore, we showed that the endogenous TRPM7-like current, which is known as Mg2+-inhibitable cation current (MIC) or Mg nucleotide–regulated metal ion current (MagNuM) in rat basophilic leukemia (RBL) cells was also significantly potentiated by acidic pH, suggesting that MIC/MagNuM is encoded by TRPM7. The pH sensitivity represents a novel feature of TRPM7 and implies that TRPM7 may play a role under acidic pathological conditions