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281.
《L'Anthropologie》2021,125(4):102910
In the early phase of the Upper Palaeolithic the cultural traditions that were expressed in lithic technology, way of life, also in various elements of symbolic culture had a complex nature. They can be divided in terms of derivation, occupied territory, chronology, and – partially – the anthropological type of a given population. The traditions whose origins were local were in all likelihood related to the Neanderthals, whereas those whose origins were exogeneous were connected with Anatomically Modern Humans. In terms of technologal-stylistics in the initial phase of the Upper Palaeolithic, we can distinguish autochthonous traditions rooted in a local Levallois or Moustero-Levallois substratum, traditions developped from a local Micoquian substratum with bifacial technology, and traditions rooted in the industries with blade and bifacial technologies of the Middle Palaeolithic. These are opposed to allochtonous traditions that can be related to the migrations of Anatomically Modern Humans from the Near East.  相似文献   
282.
To what extent do repair and maintenance of consumer electronics conserve the materials and energy they embody? In this paper we examine the conservation value of a cluster of independent third-party electronics repair businesses in Lima, Peru. Drawing on a combination of methods that include fieldwork, digital methods for online sociology, and life cycle assessment (LCA) of phones and tablets we quantify the conservation value of typical repairs performed at businesses in this cluster in terms of CO2 equivalent (CO2e) and water consumption relative to new manufactures of the same categories of electronics. We model typical repair scenarios and find that repair can offer substantial conservation benefits. However, these benefits vary by device sub-unit repaired (e.g., replacing a camera vs. replacing a display). For example, while two screen repairs through replacement is nearly equivalent to replacement with a whole new device, repairing with components that are already in the market could save around 10% of total emissions in global warming potential (GWP) for both devices. Further, we discuss the politics of attributing the conservation value achieved by the third-party repair cluster in Lima to either domestic (that is, Peruvian) or foreign CO2e and water consumption. Whose conservation of CO2e and water is this? How do the answers to that question shape understandings of the relevance of location for industrial ecology? Our work contributes to the emerging subfield of political industrial ecology and its incorporation of spatially explicit LCAs.  相似文献   
283.
In a recent article in this journal, Abram Brummett argues that new and future assisted reproductive technologies will provide challenging ethical questions relating to lesbian, gay, bisexual and transgender (LGBT) persons. Brummett notes that it is likely that some clinicians may wish to conscientiously object to offering assisted reproductive technologies to LGBT couples on moral or religious grounds, and argues that such appeals to conscience should be constrained. We argue that Brummett's case is unsuccessful because he: does not adequately interact with his opponents’ views; equivocates on the meaning of ‘natural’; fails to show that the practice he opposes is eugenic in any non‐trivial sense; and fails to justify and explicate the relevance of the naturalism he proposes. We do not argue that conscience protections should exist for those objecting to providing LGBT people with artificial reproductive technologies, but only show that Brummett's arguments are insufficient to prove that they should not.  相似文献   
284.
Methods for the identification, evaluation, and control of hazards are well recognized, whereas a method for the anticipation of hazards has eluded the field of industrial hygiene. The Emerging Technologies Team at the National Institute for Occupational Safety and Health has developed a method for anticipating not only occupational hazards but also potential benefits of emerging technologies for occupational safety and health. This method incorporates forecasting tools with a prospective assessment step into the risk assessment model, stresses research results as an iterative driver in the assessment, and depends on inherently safer design to eliminate or reduce hazards. An iterative process that involves the occupational safety and health professional as a team member in the development of emerging technologies is recommended.  相似文献   
285.
Depolarizing the GM debate   总被引:1,自引:1,他引:0  
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286.
Since the first reported birth following in vitro fertilization in 1978, further developments in assisted reproductive technology (ART) treatments have produced at least 8 million babies worldwide. Cryopreservation techniques have been central to this treatment revolution, increasing cycle efficacy by allowing the banking of supernumerary embryos for later use, as well as affording the prospective patient more time in cases of anticipated fertility decline. Additionally, these techniques have demonstrated promise in increasing the safety of ART treatments, by reducing complications such as ovarian hyperstimulation, leading to increased support for the introduction of a ‘total freeze’ policy involving deferred embryo transfers. Importantly, the effective cryopreservation of both spermatozoa and oocytes has permitted long-term gamete storage without degradation of quality, facilitating gamete banking for personal use or fertility treatment. Here, we will summarise the indications for applying cryopreservation methods in clinical reproductive medicine, highlighting recent technical advances and examining the evidence base that supports the continued use of cryopreservation in ART.  相似文献   
287.
Incorporating materials into sediment caps that can sequester contaminants will greatly improve their ability to isolate contaminants in the underlying sediments from the rest of the aquatic environment. For highly sorptive media a thin layer (cm) may be sufficient, but accurately placing a thin layer (cm) of material over submerged contaminated sediment is difficult. A reactive core mat (RCM) was designed to accurately place a 1.25 cm thick sorbent (coke) layer in an engineered sediment cap. In April 2004, twelve 3.1 m × 31 m sections of RCM were placed in the Anacostia River, Washington, D.C., and overlain with a 15 cm layer of sand to secure it and provide a habitat for benthic organisms to colonize without compromising the integrity of the cap. Placement of the RCM did not cause significant sediment re-suspension or impact site hydrology. The RCM is an inexpensive and effective method to accurately deliver thin layers of difficult to place, high value, sorptive media into sediment caps. The approach can also be used to place granular reactive media that can degrade or mineralize contaminants.  相似文献   
288.
Summary Effect of two different moisture sequences with a short period of drying between them on the changes in its sulphate levels during incubation revealed considerable immobilisation of sulphate in soils maintained either at 50% of water holding capacity or under waterlogged condition prior to drying. The extent of immobilisation was more pronounced when starch or inorganic sulphate sulphur were added. Drying resulted in release of available sulphate sulphur in the soil previously incubated at 50% of water holding capacity and the effect was more striking when starch was added. Whereas, drying caused a decrease in the amount in the soil kept under waterlogged condition. A short period of drying did release sulphate sulphur in available form.  相似文献   
289.
290.
Conventional Orthognathic surgery (OGS) planning involves cephalometric analyses and dental casts to be mounted on an articulator. Dental segments are subsequently identified, cut and repositioned to allow the fabrication of intraoral wafers that guide the positioning of the osteotomy bone segments. This conventional planning introduces many inaccuracies that affect the post-surgery outcomes. Although computer technologies have advanced computational tools for OGS planning, they have failed in providing a practical solution. Many focuses only on some specific stages of the planning process, and their ability to transfer preoperative planning data to the operating room is limited. This paper proposes a new integrated haptic-enabled virtual reality (VR) system for OGS planning. The system incorporates CAD tools and haptics to facilitate a complete planning process and is able to automatically generate preoperative plans. A clinical pre-diagnosis is also provided automatically by the system based on the patient’s digital data. A functional evaluation based on a real patient case study demonstrates that the proposed virtual OGS planning method is feasible and more effective than the traditional approach at increasing the intuitiveness and reducing errors and planning times.  相似文献   
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