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The History of Malleability: How Humans Have Shaped and Transformed the World



Purpose: Since its introduction in 1996 Mulcahy salvage has significantly improved outcomes for the removal and replacement of infected inflatable penile prostheses. Long-term followup data of Mulcahy salvage show an infection-free rate of 82%. A multicenter retrospective analysis of the malleable implant salvage technique was conducted to assess infection outcomes and the feasibility of conversion from malleable device back to inflatable penile prosthesis.




malleable



Materials and methods: This is a retrospective, institutional review board exempt, multi-institution study of 58 patients who underwent Mulcahy salvage with inflatable penile prosthesis removal and replacement with malleable prosthesis. Patient operative notes and charts were extensively reviewed to compile study data.


Results: Between 2002 and 2014 a total of 58 patients underwent infected inflatable penile prosthesis removal and replacement with a malleable prosthesis via Mulcahy salvage. Of these patients 54 (93%) have remained infection-free postoperatively. Average patient age was 56.4 years and average operative time was 148 minutes. Postoperative followup (as of May 2015) ranged from 1 month to 84 months. Of the 54 patients 37 retained the malleable prosthesis and 17 (31%) subsequently underwent replacement with an inflatable penile prosthesis. This occurred on average 6.7 months after Mulcahy salvage. Four patients had persistent infection after Mulcahy salvage with the malleable prosthesis and underwent explantation.


Conclusions: This retrospective analysis of Mulcahy salvage procedure and replacement of inflatable penile prosthesis with malleable prosthesis shows a high infection-free rate. Additionally, 17 of the 54 patients who remained infection-free were able to successfully undergo subsequent removal of the malleable prosthesis and replacement with an inflatable penile prosthesis. Further prospective studies are needed to compare salvage with malleable vs inflatable penile prosthesis.


But a new University of California, Davis, study of intermediate school students in urban California and New York shows promise for underachievers. Researchers found that early intervention with teachers, training students that intelligence is malleable and achievable, caused struggling students to flourish and improve their grades.


In the study, teachers were given a prominent role in delivering the intervention. This conveys to students, researchers said, that teachers endorse a growth mindset and believe students can improve. Teachers delivered three of every four lessons in Brainology and led students in actively processing the material. For example, teachers might ask students to identify subjects where they wanted to improve and help them design a plan for maximizing their learning in those subjects, demonstrating the concept of malleable intelligence.


One of the most intriguing features of the brain is its ability to be malleable, allowing it to adapt continually to changes in the environment. Specific neuronal activity patterns drive long-lasting increases or decreases in the strength of synaptic connections, referred to as long-term potentiation and long-term depression, respectively. Such phenomena have been described in a variety of model organisms, which are used to study molecular, structural, and functional aspects of synaptic plasticity. This review originated from the first International Society for Neurochemistry (ISN) and Journal of Neurochemistry (JNC) Flagship School held in Alpbach, Austria (Sep 2016), and will use its curriculum and discussions as a framework to review some of the current knowledge in the field of synaptic plasticity. First, we describe the role of plasticity during development and the persistent changes of neural circuitry occurring when sensory input is altered during critical developmental stages. We then outline the signaling cascades resulting in the synthesis of new plasticity-related proteins, which ultimately enable sustained changes in synaptic strength. Going beyond the traditional understanding of synaptic plasticity conceptualized by long-term potentiation and long-term depression, we discuss system-wide modifications and recently unveiled homeostatic mechanisms, such as synaptic scaling. Finally, we describe the neural circuits and synaptic plasticity mechanisms driving associative memory and motor learning. Evidence summarized in this review provides a current view of synaptic plasticity in its various forms, offers new insights into the underlying mechanisms and behavioral relevance, and provides directions for future research in the field of synaptic plasticity. Read the Editorial Highlight for this article on page 788. Cover Image for this issue: doi: 10.1111/jnc.13815.


Malleability is a property of some cryptographic algorithms.[1] An encryption algorithm is "malleable" if it is possible to transform a ciphertext into another ciphertext which decrypts to a related plaintext. That is, given an encryption of a plaintext m \displaystyle m , it is possible to generate another ciphertext which decrypts to f ( m ) \displaystyle f(m) , for a known function f \displaystyle f , without necessarily knowing or learning m \displaystyle m .


On the other hand, some cryptosystems are malleable by design. In other words, in some circumstances it may be viewed as a feature that anyone can transform an encryption of m \displaystyle m into a valid encryption of f ( m ) \displaystyle f(m) (for some restricted class of functions f \displaystyle f ) without necessarily learning m \displaystyle m . Such schemes are known as homomorphic encryption schemes.


A cryptosystem may be semantically secure against chosen plaintext attacks or even non-adaptive chosen ciphertext attacks (CCA1) while still being malleable. However, security against adaptive chosen ciphertext attacks (CCA2) is equivalent to non-malleability.[2]


Block ciphers in the cipher block chaining mode of operation, for example, are partly malleable: flipping a bit in a ciphertext block will completely mangle the plaintext it decrypts to, but will result in the same bit being flipped in the plaintext of the next block. This allows an attacker to 'sacrifice' one block of plaintext in order to change some data in the next one, possibly managing to maliciously alter the message. This is essentially the core idea of the padding oracle attack on CBC, which allows the attacker to decrypt almost an entire ciphertext without knowing the key. For this and many other reasons, a message authentication code is required to guard against any method of tampering.


Fischlin, in 2005, defined the notion of complete non-malleability as the ability of the system to remain non-malleable while giving the adversary additional power to choose a new public key which could be a function of the original public key.[3] In other words, the adversary shouldn't be able to come up with a ciphertext whose underlying plaintext is related to the original message through a relation that also takes public keys into account.


late 14c., "capable of being shaped or extended by hammering or rolling," from Old French malleable and directly from Medieval Latin malleabilis, from malleare "to beat with a hammer," from Latin malleus "hammer" (from PIE root *mele- "to crush, grind"). Figurative sense, of persons, "capable of being adapted by outside influence" is recorded from 1610s.


It forms all or part of: amyl; amyloid; blintz; emmer; emolument; immolate; maelstrom; mall; malleable; malleolus; mallet; malleus; maul; meal (n.2) "edible ground grain;" mill (n.1) "building fitted to grind grain;" millet; mola; molar (n.); mold (n.3) "loose earth;" molder; ormolu; pall-mall.


However, due to small sample sizes and lack of statistical power, these studies could not empirically test the relative association of these factors when considered all together with active learning. In addition, these studies did not account for the nested nature of their institutional contexts (i.e., instructors within departments within institutions). Therefore, a large-scale, multidisciplinary study of malleable factors (i.e., things that can be changed and altered) related to adoption of such active learning pedagogies in postsecondary STEM courses is needed to complement the research literature and provide further opportunity for actionable changes at instructor, department, and institution levels.


The study reported herein focuses specifically on instructors of introductory chemistry, mathematics, and physics and the malleable factors that influence their uptake of active learning practices as measured by a proxy, i.e., percent time not lecturing. Specifically, we use multilevel modeling to account for the nested nature of our data by discipline and institution, and evaluate 17 factors situated within the three categories (i.e., contextual factors, personal factors, and teacher thinking) as to their relationship with reported percent time lecturing. The teacher-centered systemic reform model (Gess-Newsome et al., 2003; Woodbury & Gess-Newsome, 2002) suggests that factors within these categories are related to enacted teaching practices. In the next section, we describe this conceptual framework and detail the literature that report these 17 factors related to the adoption of active learning.


In this study, we include malleable factors that have been found and discussed in many and different STEM fields as specific disciplines may lack literature in that area. While STEM fields may show some disciplinary differences, these factors can be assumed to affect all STEM fields to some extent (Lund & Stains, 2015). In the next sections, we describe the evidence-based factors grounded in the literature that have been found to affect the uptake of active learning under each of the three broad categories in the TCSR model that were tested in this study (see Fig. 1).


Conceptualization of the Teacher-Centered Systemic Reform (TCSR) model for change in higher education with control variables (discipline and highest degree awarded) and malleable factors included in this study 2ff7e9595c


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