Belief versus acceptance: Why do people not believe in evolution?

Despite being an established and accepted scientific theory for 150 years, repeated public polls show that evolution is not believed by large numbers of people. This essay examines why people do not accept evolution and argues that its poor representation in some science textbooks allows misconceptions, established and reinforced in early childhood, to take hold. There is also a lack of up‐to‐date examples of evidence for evolution in school textbooks. Poor understanding by science graduates and teachers of the nature of science and incorrect definitions by them of key terminology, serve only to undermine efforts to improve public understanding of evolution. This paper has several recommendations, including the introduction of evolution to primary age children and a call to bring evolution back as the central tenet of biology.     

Label-free detection of living cervical cells based on microfluidic device with terahertz spectroscopy

Early diagnosis of cervical cancer is essential for a good prognosis. Terahertz wave detection technology is a nondestructive and label-free physical detection technology, which can detect and monitor the cancer cells in real time, especially for patients with deep or inaccessible tumors. In this study, a single-cell-layer microfluidic device was developed. After replacing the optical clearing agent, the characteristics of H8, HeLa and SiHa cell lines in adherent and suspended states were detected. Additionally, the absorption increased with increasing cell density. For the mixed suspension cell samples, principal component analysis–support vector machine method was used to identify benign and malignant cell component. After living cells formaldehyde, changes in cell membrane permeability were evaluated to identify the cell survival status (i.e., dead or living) based on terahertz spectroscopy amplitude differences. Therefore, extending the terahertz spectrum detection to the molecular level can characterize the life essence of cells and tissues.     

Telecentric design for digital-scanning-based HiLo optical sectioning endomicroscopy with an electrically tunable lens

Confocal endoscopy has been widely used to obtain fine optically sectioned images. However, confocal endomicroscopic images are formed by point-by-point scanning in both lateral and axial directions, which results in long image acquisition time. Here, an endomicroscope with telecentric configuration is presented to achieve nonmechanical and rapid axial scanning for volumetric fluorescence imaging. In our system, optical sectioning in wide-field fashion is obtained through HiLo imaging with a digital micromirror device. Axial scanning, without mechanical moving parts, is conducted by digital focus adjustment using an electrically tunable lens, offering constant magnification and contrast. We demonstrate imaging performance of our system with optically sectioned images using fluorescently labeled beads, as well as ex vivo mice cardiac tissue samples. Our system provides multiple advantages, in terms of improved scanning range, and reduced image acquisition time, which shows great potentials for three-dimensional biopsies of volumetric biological samples.     

2021 PACES expert consensus statement on the indications and management of cardiovascular implantable electronic devices in pediatric patients

In view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients.     

The effects of excessive drilling diagnosis on decay propagation in trees

The effects of excessive drilling into the trunk with an increment borer and drilling resistance measurement device were determined for four trees of three different species (Populus nigra L., Acer pseudoplatanus L., Quercus robur L.). At the test trees with an internal decay it was found that there are two counteracting effects: First, the internal decay slightly enters into the drilling channel, which is locally a negative effect. But, on the other hand, there is the creation of a reaction zone beside the drilling hole enclosing the drilling channel in order to delay efficiently further decay propagation. Furthermore, there is the formation of a barrier zone spacious covering the location of drilling with multiple layers of fungicide tissue. These are two positive effects stopping or delaying the local outgrowth of the internal decay. Far away from the drilling hole the internal decay is not only locally coming out into the sound wall thickness but is also not specially delayed in propagation. So after some years the decay front is everywhere homogenous again, respectively, the spreading central inner decay has caught up with the migrated decay in the drilling channel. For the tree the negative effect of drilling was compensated nearly completely. In addition, it was found that in no case a decay had entered the drilling channels from outside and survived in the outer area of the drill hole.     

Dynamic cell contacts between periportal mesenchyme and ductal epithelium act as a rheostat for liver cell proliferation

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微针及其在生物诊疗中的应用研究进展

微针在过去几十年中发展迅速,在透皮给药等领域已得到了广泛的研究.近些年随着微电子技术的蓬勃兴起,微针在生物诊疗中的应用越来越多的受到人们关注.通过微针提取血液和组织液进行检测分析以及微针作为电极在体液内直接对血糖、黑色素瘤、pH值等进行实时检测方面,都展现出了良好的实时检测应用前景.文中综述了微针的材料与结构设计及其在...     

An Application of Renewal Theory to Contraceptive Follow-up Studies,Exemplified by an Intrauterine Device Study

Contraceptive practice consists of a series of recurrent events of use and nonuse. Application of the life table technique for analysis of multiple-segment contraceptive usage is not entirely satisfactory. In this paper the renewal process approach is applied to the results of contraceptive follow-up studies involving all segments of use. By means of this model, it is possible to estimate the proportion of current users, the average duration of actual use, and the average number of segments used by the acceptors. The practical importance of these parameters for the evaluation of family planning programs is considered.     

EFFECT OF THE SOUND GENERATED BY AN ACOUSTIC HARASSMENT DEVICE ON THE RELATIVE ABUNDANCE AND DISTRIBUTION OF HARBOR PORPOISES (PHOCOENA PHOCOENA) IN RETREAT PASSAGE, BRITISH COLUMBIA

We describe an experiment conducted to assess the impact of the sound generated by an acoustic harassment device (AHD) on the relative abundance and distribution of harbor porpoises ( Phocoena phocoena ) in Retreat Passage, British Columbia. During control periods when the AHD was inactive, the mean number of porpoises observed in the study area was 0.39 for broad area scans conducted with the naked eye and 0.48 for narrow sector scans conducted with binoculars. Abundance declined precipitously when the AHD was activated, to 0.007 porpoises per broad area scan and 0.018 per narrow sector scan. The mean number of porpoise resightings while tracking their movements also declined from 12.2 to 13.6 per sighting during control periods to 1.1–1.9 per sighting when the AHD was activated, which suggested that the few porpoises that ventured into the study area spent less time within it when the AHD was activated. The effect of the AHD diminished with distance. No porpoises were observed within 200 m of the AHD when it was activated. The number of sightings and resightings observed when it was activated was less than 0.2% of the number expected had there been no AHD effect at a range of 200–399 m, 1.4% the number expected at a range of 400–599 m, varied between 2.5% and 3.3% of the number expected at a range of 600–2,499 m, and was 8.1% the number expected at a range of 2,500–3,500 m, which suggested that the impact of the AHD extended beyond our maximum sighting range of 3.5 km.