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Bluetooth is a pervasive wireless technology specified in an open standard. The standard defines Bluetooth Classic (BT) for high-throughput wireless services and Bluetooth Low Energy (BLE) very low-power ones. The standard also specifies security mechanisms, such as pairing, session establishment, and cross-transport key derivation (CTKD). CTKD enables devices to establish BT and BLE security keys by pairing just once. CTKD was introduced in 2014 with Bluetooth 4.2 to improve usability. However, the security implications of CTKD were not studied carefully., This work demonstrates that CTKD is a valuable and novel Bluetooth attack surface. It enables, among others, to exploit BT and BLE just by targeting one of the two (i.e., Bluetooth cross-transport exploitation). We present the design of the first cross-transport attacks on Bluetooth. Our attacks exploit issues that we identified in the specification of CTKD. For example, we find that CTKD enables an adversary to overwrite pairing keys across transports. We leverage these vulnerabilities to impersonate, machine-in-the-middle, and establish unintended sessions with any Bluetooth device supporting CTKD. Since the presented attacks blur the security boundary between BT and BLE, we name them BLUR attacks. We provide a low-cost implementation of the attacks and test it on a broad set of devices. In particular, we successfully attack 16 devices with 14 unique Bluetooth chips from popular vendors (e.g., Cypress, Intel, Qualcomm, CSR, Google, and Samsung), with Bluetooth standard versions of up to 5.2. We discuss why the countermeasures in the Bluetooth are not effective against our attacks, and we develop and evaluate practical and effective alternatives.

We present an attack on the encryption key negotiation protocol of Bluetooth BR/EDR. The attack allows a third party, without knowledge of any secret material (such as link and encryption keys), to make two (or more) victims agree on an encryption key with only 1 byte (8 bits) of entropy. Such low entropy enables the attacker to easily brute force the negotiated encryption keys, decrypt the eavesdropped ciphertext, and inject valid encrypted messages (in real-time). The attack is stealthy because the encryption key negotiation is transparent to the Bluetooth users. The attack is standard-compliant because all Bluetooth BR/EDR versions require to support encryption keys with entropy between 1 and 16 bytes and do not secure the key negotiation protocol. As a result, the attacker completely breaks Bluetooth BR/EDR security without being detected. We call our attack Key Negotiation Of Bluetooth (KNOB) attack. The attack targets the firmware of the Bluetooth chip because the firmware (Bluetooth controller) implements all the security features of Bluetooth BR/EDR. As a standard-compliant attack, it is expected to be effective on any firmware that follows the specification and on any device using a vulnerable firmware. We describe how to perform the KNOB attack, and we implement it. We evaluate our implementation on more than 14 Bluetooth chips from popular manufacturers such as Intel, Broadcom, Apple, and Qualcomm. Our results demonstrate that all tested devices are vulnerable to the KNOB attack. We discuss countermeasures to fix the Bluetooth specification and its implementation.

Introduction. Metastases are the most common type of malignancy involving the bone, while bone is the third most frequent site for metastases, after the lung and liver. In some patients, medical history, physical and laboratory examination are not conclusive to identify the primary tumor site. In such cases a bone biopsy and immunohistochemical analysis may contribute to the diagnosis, determination of appropriate treatment and evaluation of prognosis. In this study, we tried to evaluate the imunochistochemical expression in bone metastases. Material and methods. We reviewed 125 patients, with a mean age of 63 years, treated for bone metastases in our institution. All patients received palliative orthopaedic surgery for bone metastatic carcinoma. Fifty-eight patients had already an established diagnosis of the primary tumor, while 67 patients presented metastases with an unknown primary tumor origin. Immunohistochemical analysis was performed to intra-operative bone biopsy specimens. The expression of cytokeratine 7, cytokeratin 20 and the expression of a panel of other organ-specific markers were recorded. In patients with a known primary tumor, we examined the relationship between the origin of metastases, as suggested by the cytokeratin phenotype, compared with the one indicated by the initial histological diagnosis. We also recorded the efficacy of organ-specific markers to identify the primary tumor origin in epithelial bone metastases and we evaluated the prognosis between patients with a immunohistologically determined primary tumor origin, with those with an undetermined one. Results. Associations of cytokeratine 7 and cytokeratine 20 expression confirmed diagnosis in 51 out of the 58 patients (88%) with a known primary tumor (Cohen's K test 0.79 SE 0.80, P < 0.0005). Immunohistochemical analysis also contributed to establish the diagnosis of patients with an unknown primary tumor, yielding diagnosis in 35 out of the 67 cases (52%). Patients with an immunochistologically undetermined primary tumor site presented a statistically significant poorer prognosis. Conclusions. Cytokeratine 7 and cytokeratine20 are useful immunochistochemical markers in determining a preliminary evaluation of bone metastases. Organ-specific immunohistochemical markers have a reliable role in either suggesting or confirming the possible origin of metastases. An indeterminate immunohistochemical phenotype seems to relate to a less differentiated lesion, with a worse prognosis. © Polskie Towarzystwo Onkologiczne.

This paper reports on the synthesis and physico-chemical, mechanical, and biological characterization of two sets of poly(amidoamine) (PAA) hydrogels with potential as scaffolds for in vivo peripheral nerve regeneration. They are obtained by polyaddition of piperazine with N,N′-methylenebis(acrylamide) or 1,4-bis(acryloyl)piperazine with 1,2-diaminoethane as cross-linking agent and exhibit a combination of relevant properties, such as mechanical strength, biocompatibility, biodegradability, ability to induce adhesion and proliferation of Schwann cells (SCs) preserving their viability. Moreover, the most promising hydrogels, that is those deriving from 1,4-bis(acryloyl)piperazine, allow the in vitro growth of the sensitive neurons of the dorsal root ganglia, thus getting around a critical point in the design of conduits for nerve regeneration. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Background Many tools are available to estimate prediction quality, but none are available to assess the ability, of a predictive model to identify completely missing or unknown prognostic factors, designated as ghost factors (GFs). However, it may be possible to predict whether a subject carries a GF. Methods To simulate the presence of a GF, a significant prognostic factor and all variables correlated with it were removed prior to model analysis. Public datasets and simulated data were used. A predictive statistical model was developed to assess the relationship between the presence of a GF and the predictive capacity of a given model based on the correlation between predicted outcome and GF presence. Five statistical models were compared using this procedure. Results After evaluating 6 real databases, the only statistical method consistently able to identify subjects with GFs was the use of optimized regression models. Using simulated, linearly correlated data, optimized regression models exhibited up to a 92% success rate, whereas conventional linear models had less than 53% success. Random forest and classification tree models had the highest success rates compared to the other evaluated models. Conclusions Model-based outcome prediction was assessed with respect to the presence of GFs. As GFs are unknown, only subjects who are carriers of significant unknown prognostic factors can be identified. As complex models outperformed linear models in identifying GF presence, we assume that the associations between GFs and outcome-predictive factors are also complex and not linear.

Even though many scales for the assessment of sexual dysfunction have been recently developed, most of them are suitable rather for the research purpose in clinical trials than to routine interviews in a daily, private practice. We report here the first experience with a simple, semi-quantitative scale for parallel assessment of sexual dysfunction and life-satisfaction (considered to globally reflect the quality of life), which was tested in depressed patients treated in the psychiatric, private practice setting. A combined Sexual Dysfunction(SD-S) and Life-Satisfaction Scale (LS-S), was constructed based on previous interviews with patients. Both consisted of 4-items, assumed to represent core elements of sexual function and individual well-being. The scales were applied to depressed patients treated with any of the SSRIs or with moclobemide, a reversible and selective MAO-A inhibitor. These two treatments were selected for testing the scales because it is known that SSRIs can induce or exacerbate them and moclobemide does not seem to affect them. The selection of treatment modality in this study was, however, entirely at the discretion of the physician. The assessments were done during 3 visits (at baseline, after 2 months and after 4 months). The results of this exploratory trial, testing the applicability, acceptance and utility of a combined mini- SD-S- and LS-S- scale, in 62 depressed patients, showed that the scale: a) was simple to use and well accepted by physicians and patients, b) was a suitable instrument for the practicing physician to control the success of the treatment and c) was sensitively assessing the presence and severity of sexual dysfunction., EXCLI Journal ; Vol. 3, 2004