Discovery of a new 2.3 s isomer in neutron-rich 174Tm

A new program of K-isomer research has been initiated with the 8π spectrometer sited at the ISAC facility of TRIUMF. We discuss in this paper the identification of a new 2.3 s isomer in 174Tm and its implications. © Società Italiana di Fisica / Springer-Verlag 2005.

Biomimetic calcium carbonate-gelatin composites as a model system for eggshell mineralization

The composite nature of mineralized natural materials is achieved through both the microstructural inclusion of an organic component and an overall microstructure that is controlled by templating onto organic macromolecules. A modification of an existing laboratory technique is developed for the codeposition of a CaCO3-gelatin composite with a controllable organic content. First, calibration curves are developed to determine the organic content of a CaCO3-gelatin composite from infrared spectra. Second, a CaCO3-gelatin composite is deposited on either glass coverslips or demineralized eggshell membranes using an automated alternating soaking process. Electron microscopy images and use of the infrared spectra calibration curves show that by altering the amount of gelatin in the ionic growth solutions, the final organic component of the mineral can be regulated over the range of 1-10%, similar to that of natural eggshell. © 2012 Materials Research Societ.

Coupling model uncertainty for coupled rainfall/runoff and surface water quality models in river problems

Coupled hydrology and water quality models are an important tool today, used in the understanding and management of surface water and watershed areas. Such problems are generally subject to substantial uncertainty in parameters, process understanding, and data. Component models, drawing on different data, concepts, and structures, are affected differently by each of these uncertain elements. This paper proposes a framework wherein the response of component models to their respective uncertain elements can be quantified and assessed, using a hydrological model and water quality model as two exemplars. The resulting assessments can be used to identify model coupling strategies that permit more appropriate use and calibration of individual models, and a better overall coupled model response. One key finding was that an approximate balance of water quality and hydrological model responses can be obtained using both the QUAL2E and Mike11 water quality models. The balance point, however, does not support a particularly narrow surface response (or stringent calibration criteria) with respect to the water quality calibration data, at least in the case examined here. Additionally, it is clear from the results presented that the structural source of uncertainty is at least as significant as parameter-based uncertainties in areal models. © 2012 John Wiley & Sons, Ltd.

视觉密码方案的构造

视觉密码学是在最近十余年间逐渐发展起来的新型密码学分支。近年从事视觉密码学研究的学者越来越多，研究结果频现于三大密码学会和Journal of Cryptology, Designs, codes and cryptography和IEEE Transactions on Image Processing等高水平期刊上。视觉密码方案（VCS）具有的针对图片加解密，视觉解密，秘密共享和无条件安全等特点，较之传统的秘密共享方案，它具有解密设备简单的优点，解密过程不需要使用者拥有任何密码学知识，可以直接观察到解密图片。而较之传统的秘密隐藏方案，他具有信息容量大的优点，可以加密整幅图片的秘密信息，而且由于其加解密的对象是图片，因此其信息内容可以灵活多变。视觉密码方案可以应用在秘密共享，信息隐藏，身份认证/鉴别以及版权保护等方面。随着具有更多特殊性质的视觉密码方案的提出，其应用范围也会越来越广。本文的工作主要集中在两个方面：视觉密码方案的构造和分析以及视觉密码相关问题的研究。 在视觉密码方案的构造和分析方面，本文所做的工作主要包括： 本文在第二章提出一个利用嵌入技术构造有意义分享图片视觉密码方案（EVCS）的方法。与已知的构造相比，其优点包括：(1) 可以直接处理灰度图片；(2) 具有较小的秘密图片像素扩张；(3) 可以针对一般存取结构构造，且总是无条件安全的；(4)每个参与者只分配一张分享图片；(5) 具有在分享图片像素扩张、分享图片视觉效果和秘密图片像素扩张之间相互取舍的灵活性。 本文在第三章提出了一种针对一般存取结构的VCS的递归构造方法，与过往的VCS相比，在大多数存取结构下，本文的方法在平均像素扩张，像素扩张和对比度方面都有所改进。根据本文的构造方法，可知针对一般存取结构的VCS的构造可以通过递归调用(2,2)-VCS来实现，而无论其所基于的是“OR”还是“XOR”运算。本文的方案最终可能分配给某个参与者多张分享图片，由于平均像素扩张的降低，因此这一点并不能称之为缺点。另外，利用本文中的方案可以构造出针对一般存取结构的基于“XOR”运算的VCS。 对于彩色视觉密码方案（CVCS），基于Naor-Shamir视觉密码模型，本文在第四章提出一个的没有像素扩张的(k,n)-CVCS，以及与对应的黑白(k,n)-EVCS具有相同像素扩张的(k,n)-CEVCS；基于Tuyls视觉密码模型，本文首先分别提出了黑白(k,n)-VCS和黑白(k,n)-EVCS，并以此为构件提出(k,n)-CVCS和(k,n)-CEVCS。仿真实验结果表明，本文提出的方案具有较好的视觉效果。 对于防止欺骗的视觉密码方案，本文在第五章首先分析了已知的几种防止欺骗的视觉密码方案（CIVCS）的缺陷，然后提出一个新的CIVCS来避免这些缺陷。本文所提出的CIVCS构建于已知的VCS之上，在只泄漏极少量秘密图片的信息的情况下达到了很高的安全性。并且可以针对一般存取结构。本文所提出的CIVCS也可以应用在底层运算为“XOR”运算的VCS之上。另外，本文所提出的CIVCS可以根据参与者携带验证信息的多少，可以检测出欺骗行为或者可以揪出具体的欺骗者。 本文在第六章研究了基于“XOR”运算的(2,n)-VCS的最优化问题。给出了基于“XOR”运算的(2,n)-VCS的最小像素扩张，以及具有最小像素扩张条件限制下的最大对比度和最大平均对比度。另外给出了基于“XOR”运算的(2,n)-VCS的最大对比度，以及具有最大对比度条件限制下的最小像素扩张。上述四类方案在本文中都给出了具体的构造方法，以及相关对比度，像素扩张和基矩阵的结构性质的证明。本文中的结果表明基于“XOR”运算下的(2,n)-VCS的各个参数都要比基于“OR”运算下的对应的参数要好。本文还证明了构造具有最大对比度的(2,n)-VCS的基矩阵等价于构造具有相应参数且达到最大容量的二元码。故根据本文的研究结果，便可以通过利用已知的构造达到最大容量的二元码的方法来构造具有最大对比度的(2,n)-VCS，最后对于n=2^k-1的情况，本文还给出了一个利用m-序列来构造具有最大对比度的(2,n)-VCS的方法。 本文在第七章证明了Droste提出的基于“OR”运算的(k,n)-VCS同样在“XOR”运算下也成立。同时基于“OR”运算和“XOR”运算的VCS会给参与者带来便利，他们可以根据不同的环境而选择不同的视觉密码模型。另外，本文还提出一个进一步降低VCS的像素扩张的方法，与Tuyls等人所提出的(k,n)-VCS比较，本文的方法可以显著的降低方案的像素扩张。本文在第七章还提出一个可以运行在Tuyls视觉密码模型之上的同色(k,n)-VCS的构造方法，其中每个分享图片都是同色的，而叠加k个分享图片可以得到黑白的秘密图片。本文证明了当k为奇数时，同色的(k,n)-VCS是不存在的，并给出了当k为偶数时，同色(k,n)-VCS的构造方法。同色(k,n)-VCS可以用来防止分享图片被隐蔽的监控摄像头窃取。 在视觉密码相关问题的研究方面，本文所做的工作主要包括： 本文在第八章研究了视觉密码方案的幻灯片对齐问题，证明了，在幻灯片没有精确对齐的情况下，人眼仍能观察到秘密图片，且其平均对比度满足-(m-r)e/(m2(m-1))。这项研究可以为确定幻灯片中像素的尺寸做参考。本研究也证明了视觉密码方案本身具有一定的纠错能力。 本文在第九章研究了视觉密码中的对比度定义的表示问题。首先给出了四个关于VCS对比度的观察结论，并分析了已知的几种对比度定义的缺陷，从而提出了一个新的对比度定义。本文在理论和实验上说明了，其所提出的对比度定义符合上述观察结论，可以更精确的衡量所恢复的秘密图片的视觉效果。本文最后还针对概率视觉密码方案的定义给出了针对概率视觉密码方案的对比度的定义。 最后我们对本文的工作进行了总结，并对今后的一些研究方向进行了展望。

A uniform, quality controlled Surface Ocean CO2 Atlas (SOCAT)

A well documented, publicly available, global data set of surface ocean carbon dioxide (CO2) parameters has been called for by international groups for nearly two decades. The Surface Ocean CO2 Atlas (SOCAT) project was initiated by the international marine carbon science community in 2007 with the aim of providing a comprehensive, publicly available, regularly updated, global data set of marine surface CO2, which had been subject to quality control (QC). Many additional CO2 data, not yet made public via the Carbon Dioxide Information Analysis Center (CDIAC), were retrieved from data originators, public websites and other data centres. All data were put in a uniform format following a strict protocol. Quality control was carried out according to clearly defined criteria. Regional specialists performed the quality control, using state-of-the-art web-based tools, specially developed for accomplishing this global team effort. SOCAT version 1.5 was made public in September 2011 and holds 6.3 million quality controlled surface CO2 data points from the global oceans and coastal seas, spanning four decades (1968–2007). Three types of data products are available: individual cruise files, a merged complete data set and gridded products. With the rapid expansion of marine CO2 data collection and the importance of quantifying net global oceanic CO2 uptake and its changes, sustained data synthesis and data access are priorities.

A uniform, quality controlled Surface Ocean CO2 Atlas (SOCAT)

A well-documented, publicly available, global data set of surface ocean carbon dioxide (CO2) parameters has been called for by international groups for nearly two decades. The Surface Ocean CO2 Atlas (SOCAT) project was initiated by the international marine carbon science community in 2007 with the aim of providing a comprehensive, publicly available, regularly updated, global data set of marine surface CO2, which had been subject to quality control (QC). Many additional CO2 data, not yet made public via the Carbon Dioxide Information Analysis Center (CDIAC), were retrieved from data originators, public websites and other data centres. All data were put in a uniform format following a strict protocol. Quality control was carried out according to clearly defined criteria. Regional specialists performed the quality control, using state-of-the-art web-based tools, specially developed for accomplishing this global team effort. SOCAT version 1.5 was made public in September 2011 and holds 6.3 million quality controlled surface CO2 data points from the global oceans and coastal seas, spanning four decades (1968–2007). Three types of data products are available: individual cruise files, a merged complete data set and gridded products. With the rapid expansion of marine CO2 data collection and the importance of quantifying net global oceanic CO2 uptake and its changes, sustained data synthesis and data access are priorities.

Surface Ocean CO2 Atlas (SOCAT) gridded data products

As a response to public demand for a well-documented, quality controlled, publically available, global surface ocean carbon dioxide (CO2) data set, the international marine carbon science community developed the Surface Ocean CO2 Atlas (SOCAT). The first SOCAT product is a collection of 6.3 million quality controlled surface CO2 data from the global oceans and coastal seas, spanning four decades (1968–2007). The SOCAT gridded data presented here is the second data product to come from the SOCAT project. Recognizing that some groups may have trouble working with millions of measurements, the SOCAT gridded product was generated to provide a robust, regularly spaced CO2 fugacity (fCO2) product with minimal spatial and temporal interpolation, which should be easier to work with for many applications. Gridded SOCAT is rich with information that has not been fully explored yet (e.g., regional differences in the seasonal cycles), but also contains biases and limitations that the user needs to recognize and address (e.g., local influences on values in some coastal regions).

Polycyclic aromatic hydrocarbons (PAHS) (I): Measures of prevention and control

Measures of prevention and control against polycyclic aromatic hydrocarbons (PAHs) focus on an official food control, a code of best practice to reduce PAHs levels by controlling industry and in the development of a chemopreventive strategy. Regulation (EU) 835/2011 establishes maximum levels of PAHs for each food group. In addition, Regulations (EU) 333/2007 and 836/2011 set up the methods of sampling and analysis for its official control. Scientific studies prove that the chemopreventive strategy is effective against these genotoxic compounds effects. Most chemopreventive compounds studied with proven protective effects against PAHs are found in fruit and vegetables.

Social Work and theatre: considering intersections

Theatre is a cultural and artistic form that involves a process of communication between creators and is received in a space and time located in the public sphere, which has meant that, over the centuries, it has acted as a space for expression, exchange and debate regarding all manner of ideas, causes and struggles. Implicit within this process are processes of expression, creation and reception, by way of which people demonstrate, analyse and question ways of seeing and understanding life, and ways of being and existing in the world. This gives rise to educational, cultural, social and political potential, which has been endorsed in numerous studies and investigations. In this work, in which theoretical orientation is established through a review of the relevant literature, we consider different intersections that occur between theatre and social work in order to also show that dramatic and theatrical expression offers substantive methodologies for achieving some objectives of social work, particularly in areas such as critical literacy, reflexivity and recognition, awareness raising, social participation, personal and/or community development, ownership of cultural capital and access to personal and social wellbeing.

Society, theatre and Social Work: beauty will save us

Three different worlds, sometimes concentric and often intersecting —society, theatre and the art of performance— and social work. Diverse worlds that live, reflect and self-reflect and interact, and can also afford an opportunity for meeting, misunderstanding and confrontation, and above all offer the possibility of profound change.This article considers the experience of a theatre company that has spent more than three years moving at the limits of these three universes. To these three worlds can be added an infinite number of words that fill them with meaning and significance: territory, meeting, diversity and search. An artistic experience that has chosen to focus on creating scenarios for debate and to examine the difficulties, the human contradictions and the constant and inexhaustible confrontation with human experience. At the heart of this theatrical activity is all of this, seeking the balance between narration, meeting, investigation and the artistic dimension. This meeting between society, theatre and social work also contains the search for sustainability of this cultural business, in an Italy that has been destroyed by a crisis that is not merely economic, but also of values and, above all, of role models. The guiding theme, though not always made explicit, is always present and essential: the search for beauty.