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We present prevalent results concerning generalized versions of the $T_p^\alpha$ spaces, initially introduced by Calderón and Zygmund. We notably show that the logarithmic correction appearing in the quasi-characterization of such spaces is mandatory for almost every function; it is in particular true for the Hölder spaces, for which the existence of the correction was showed necessary for a specific function. We also show that almost every function from $T_p^α (x0 )$ has α as generalized Hölder exponent at $x_0$.

Background:Roux-en-Y gastric bypass is a frequently carried out bariatric procedure, proven to be effective in the management of obesity and its accompanying health issues. Following its popularity, admission to the emergency department for abdominal pain is often seen with known early and late onset causes. We present a case of a young woman with vague abdominal pain years after her gastric bypass, who eventually underwent a resection of a 'candy cane' like biliopancreatic blind loop. Methods:A healthy 23-year-old woman has been suffering of vague abdominal complaints after a gastric bypass procedure 4 years earlier. Postprandial pain, diarrhoea and abdominal distension were present at a daily to weekly basis. Several investigations and management options were administered by surgeons, gastroenterologists as well as endocrinologists. On a performed explorative laparoscopy, a large blind loop at the entero-enteric anastomosis was seen and resected. Results:At current follow-up of 15 months the resection of the candy cane like blind end of the biliopancreatic loop resulted in a complete withdrawal of our patient's symptoms. A tentative diagnosis of bacterial overgrowth in the blind loop was made. Conclusions:Abdominal pain after gastric bypass is a frequent cause of admission to the emergency department. Besides the more serious complications, internal hernia is often withheld as possible diagnosis in the differential diagnosis of late onset, postprandial epigastric pain. This case report highlights another possibility. At initial surgery, a candy cane shaped blind loop should be avoided both at the gastro-jejunal as well as the entero-enteric anastomosis.

In this contribution, we present developments aiming at overcoming remaining challenges for an industrial process integration of passivating contact technologies. In particular, SiC x -based hole and electron passivating contacts activated respectively during a short and a long annealing step are developed. Implied Voc's up to 730mV have been obtained on symmetrical structures featuring SiC x (p) layers having undergone short annealing, and above 750mV for those featuring SiC x (n) submitted to long annealing. Finally, these contacts are implemented as easy add-ons in existing industrial PERC/PERT like cell architectures. First integration tests of SiC x (p) in PERC like cell featuring front phosphorous emitter have led to Voc of 686mV and cell efficiency up to 21.7% on 6inch p-type Cz. Integration of SiC x (n) in PERT like solar cells featuring a front boron emitter enabled Voc of 691mV and efficiency of 22.5% on 6 inch n-type Cz.

This work presents the upscaling of the tunnel IBC technology on large area, Czochralski (Cz) n-type wafers. At the junction level, a self-aligned PECVD masking technology has been developed for the deposition of hydrogenated nano-crystalline silicon (nc-Si:H) layers on industrial 6-inch pseudo-square wafers. This damage free patterning technology allows state-of-the-art passivation with a minority carrier lifetime of 9 ms at an injection level of 1015 cm-3, thus enabling extremely long diffusion lengths up to several millimetres. The use of indium-free, cost effective aluminium-doped zinc oxide strongly reduces the materials bill of the tunnel-IBC technology while maintaining very low contact resistance for both the electron and the hole contacts. Remarkably, these tunnel-IBC devices demonstrated a conversion efficiency of 25% on large area (90.25 cm2) industrial wafer with a thickness of 155 μm. Series resistance analysis points out probable losses from the hole contact and the base. The limitation of the Transfer Length Method is discussed when used to extract the hole contact resistance.

Carrier-selective passivating contacts have been demonstrated to be crucial to reach the practical efficiency limit of single junction, crystalline silicon (c-Si) based solar cells. Yet, the electrical transport losses affecting the collection of photogenerated carriers remain to be addressed. To this aim, different methodologies and characterization techniques are currently used. In this contribution, we propose the concept of shell as a new terminology to describe carrier-selective passivating contacts. Then, we present a novel characterization methodology using transfer length method (TLM) measurement under variable illumination to investigate the charge-carrier transport in amorphous/crystalline silicon heterojunction (SHJ) n-type contact stacks. We use technology computer-aided design simulation to model a TLM structure and to identify the physical phenomena and the key parameters affecting the contact resistivity ( ρ c ) and the charge carrier accumulation of such contact stacks. Then, the simulation results are compared with experimental data by performing variable-illumination TLM measurements of actual SHJ n-type contact stacks. Specifically, we demonstrate that illumination has a strong impact on the measured ρ c value, highlighting the importance of measuring ρ c under maximum power point conditions for a relevant characterization of solar cell transport losses. In addition, we investigate the dependence of ρ c to a change in the injected carrier density within the c-Si bulk to compare the illumination responses of different SHJ n-type contact stacks. In the quest for maximal efficiency, this method may insightfully complete other characterization techniques to further understand and study the electrical transport in solar cells.

Silicon heterojunction technology (HJT) enables record efficiencies for silicon-based solar cells [1]. The main advantage is the excellent surface passivation offered by hydrogenated amorphous silicon (a-Si:H), enabling record open circuit voltages. On the other hand, the need to use transparent conducting oxides for contacting and current spreading combined with a-Si:H leads to parasitic absorption and thus sub optimal short circuit current (JSC) for both side contacted solar cells. As a result, the advantage of this technology versus competing ones is particularly evident for back contacted solar cells [1]. However, thanks to the reduced complexity, and thus lower cost per watt, both side contacted solar cells have a much higher market penetration. It is therefore highly desirable to reduce as much as possible this parasitic absorption. In this context, high mobility TCOs like hydrogen doped indium oxide (IO:H) offers mobilities in excess of 100 cm2/(V.s) and enables higher JSC than use of the industrial standard indium tin oxide (ITO) [2]. Process control, in particular the incorporation of hydrogen, is however challenging with this material. We propose here the use of indium tungsten oxide (IWO) deposited by RF sputtering as a high mobility TCO for use in HJT solar cells. Preparing this TCO in standard conditions, i.e. with a base pressure below 5 E-7 mbar in our Oerlikon Clusterline tool already leads to mobilities higher than our best ITO process (>50 vs ~30 cm2/(V.s)) for conditions compatible with HJT solar cell processing. Furthermore, by controlling the chamber base pressure and using only argon and oxygen as reactive gases we are able to tailor the material properties to even higher mobilities (>80 cm2/(V.s)) without needing a water source or hydrogen line for doping. These layers were successfully included in HJT solar cells as evidenced by the current and efficiency gains associated with the use of this TCO.

Recently, new cycles, associated with periods of 30 and 43 months, respectively, have been observed by the authors in surface air temperature time series, using a wavelet-based methodology. Although many evidences attest the validity of this method applied to climatic data, no systematic study of its efficiency has been carried out. Here, we estimate confidence levels for this approach and show that the observed cycles are significant. Taking these cycles into consideration should prove helpful in increasing the accuracy of the climate model projections of climate change and weather forecast.

This paper reports on the development of an innovative back-contacted crystalline silicon solar cell with passivating contacts featuring an interband tunnel junction at its electron-collecting contacts. In this novel architecture, named “tunnel-IBC”, both the hole collector patterning and its alignment to the electron collector are eliminated, thus drastically simplifying the process flow. However, two prerequisites have to be fulfilled for such devices to work efficiently, namely (i) lossless carrier transport through the tunnel junction and (ii) low lateral conductance within the hole collector in order to avoid shunts with the neighboring electron-collecting regions. We meet these two contrasting requirements by exploiting the anisotropic and substrate-dependent growth mechanism of n- and p-type hydrogenated nano-crystalline silicon layers. We investigate the influence of the deposition temperature and the doping gas concentration on the structural and the selectivity properties of these layers. Eventually, tunnel-IBC devices integrating hydrogenated nano-crystalline silicon layers have been processed and demonstrate up to 23.9 % conversion efficiency.

The drop in passivation usually observed after the deposition of the p-doped amorphous silicon (a-Si:H) layer on top of the passivating intrinsic buffer a-Si:H layer during the fabrication of silicon heterojunction (SHJ) solar cells is shown to be mostly related to the properties of the i-layer itself. After optimization of the i-layer to reduce this loss, minority carrier lifetimes above 50 ms were achieved on very lowly doped wafers, and close to 18 ms on actual SHJ cell precursors with i-layers as thin as 4 nm. These films were integrated into SHJ solar cells fabricated with industry-compatible processes, yielding efficiencies up to 23.1 % on large-area devices and up to 23.9% on 4 cm2 devices. In addition, the developed a-Si:H layers were also used as key building blocks in more advanced high-efficiency solar cell architectures, such as interdigitated back-contacted SHJ solar cells (>23%), III-V//SHJ tandems (>30%), and perovskite//SHJ tandems (>25%), for example.

Self-textured zinc oxide polycrystalline films prepared by metalorganic low-pressure chemical vapor deposition combine excellent transparency, conductivity and light-scattering ability when used as electrodes for high-efficiency thin-film silicon solar cells. However, the growth of silicon layers with low defect density, which are necessary for high-performance solar cells, often requires the rough surface morphology of as-deposited zinc oxide films to be smoothened. This is usually achieved by a post-deposition argon plasma-etching treatment. We investigate here an alternative method to modify the surface morphology by changing the zinc oxide growth conditions over only the last hundreds of nanometers of the total film thickness. We discuss two types of zinc oxide cap layers, one grown with the addition of ethanol and the other with an enhanced diethylzinc (DEZ) precursor flow. We show that the presence of either type of cap layer does not alter the layer's electrical properties, but does slightly diminish the layer's light-scattering ability. The cap layer grown with ethanol leads to a more pronounced leveling of the film texture, while the high-DEZ-grown layer better preserves the sharp features of the underlying ZnO. Finally, zinc oxide films with cap layer are used as front electrodes for tandem amorphous/microcrystalline silicon solar cells, and are compared to rough films treated with an argon plasma. With rising thickness of the capping layers, the efficiency of tandem cells increases reaching values over 12%, and approaches that of cells on Ar plasma treated ZnO films. (C) 2014 Elsevier B.V. All rights reserved.

Recently, it has been shown that it is possible to tune the morphology of zinc oxide films deposited by low-pressure metalorganic chemical vapor deposition (LP-MOCVD) while preserving good electrical conductivity. Here a closer look is taken at films deposited under two different deposition conditions; one leading to LP-MOCVD a-texture (i.e., with the a-axis perpendicular to the substrate), the other resulting in c-texture (i.e., with the c-axis perpendicular to the substrate), with the aim of correlating their structural and electrical characteristics. We introduce the concept of a "selection layer" to indicate the initial region of growth that precedes the establishment of a clear preferential crystallographic film orientation. With a strong preferential c-texture of initial nucleation the selection layer for c-texture films is minimal (

ZnO bilayer films were deposited by low-pressure chemical vapor deposition in a single process step by controlling the differential doping of the nucleation and bulk parts of the layers. The resulting 2-μm-thick films are characterized by low free-carrier absorption and electron mobility over 40 cm2 /Vs. They, therefore, combine high transparency in the infrared region and moderate sheet resistance that can be lowered below 20 Ω/sq. These properties make ZnO bilayers ideal candidates as electrodes for the development of micromorph thin-film solar cells with enhanced photogenerated current. The potential of such bilayer front electrodes for a further power improvement and cost reduction of industrial micromorph tandem modules is currently investigated at Oerlikon Solar. The first experiments already show a promising gain in the bottom μc-Si:H cell photogenerated current compared with the current generated with modules deposited on standard uniformly doped ZnO single-layer front contacts.

Optimized transparent conductive oxide front electrodes are vital to further increase the efficiency of thin film silicon solar devices. We report details on the fabrication of multiscale textured zinc oxide substrates and their implementation in amorphous silicon/microcrystalline silicon tandem (micromorph) devices. Such substrates allow separate optimization of light trapping in the top and bottom cells and efficient decoupling of transparency and conduction. We show in particular the need for sharp nanoscale texturing for antireflection and light trapping in the top cell. We also show that smooth micrometer scale texturing can efficiently improve large wavelength light management without degrading the quality of the silicon material grown on the substrate. By combining the appropriate morphologies high currents can be reached in both the top and bottom subcells while conserving the optimal electrical properties of the solar cells. © 2011 IEEE.

We use the discrete "wavelet transform microscope" to study the monofractal nature of surface air temperature signals of weather stations spread across Europe. This method reveals that the information obtained in this way is richer than previous works studying long range correlations in meteorological stations: the approach presented here allows to bind the Hölder exponents with the standard deviation of surface pressure anomalies, while such a link does not appear with methods previously carried out.

CSEM in its photovoltaic activity has developed white solar modules with conversion efficiencies above 10%. This innovative PV technology is particularly attractive to be used in building industry where PV elements can blend into building skin and become virtually hidden energy sources. The new Swiss company called Solaxess is now working on the industrialization of this new technology and the first products are expected to be in the market at the end of 2015.

We use the continuous wavelet transform to perform a space-scale analysis of the AT and GC skews (strand asymmetries) in human genomic sequences, which have been shown to correlate with gene transcription. This study reveals the existence of a characteristic scale l c ≃25±10 kb that separates a monofractal long-range correlated noisy regime at small scales (l lc). We show that these large scale nonlinear oscillations enlighten an organization of the human genome into adjacent domains ( ≈400 kb ) with preferential gene orientation. When using classical techniques from dynamical systems theory, we demonstrate that these relaxational oscillations display all the characteristic properties of the chaotic strange attractor behavior observed nearby homoclinic orbits of Shil'nikov type. We discuss the possibility that replication and gene regulation processes are governed by a low-dimensional dynamical system that displays deterministic chaos.

Silicon heterojunction solar cell technology (HJT) takes advantage of ultra-thin amorphous silicon layers deposited on both sides of monocrystalline silicon wafers, enabling excellent silicon wafer surface passivation resulting in high device power output and in addition to efficient use of thin wafers. A full cell processing platform was developed in our laboratory, enabling to achieve > 22 % cell efficiency. Advanced concepts for metallization and interconnection are under study, from fine-line printing combined with SmartWire interconnection to Copper plating. Importantly, we show that the HJT technology intrinsically enables high bifaciality of the cells (> 95 %), and further demonstrates a low thermal coefficient (< 0.2 – 0.3 %/°C). The high performance of heterojunction cells and SmartWire interconnection based modules allow for very low cost of electricity for Heterojunction based solar systems, with a potential below 6 Euro cents per kWh in Europe, bringing photovoltaics as a very competitive electricity source. It further provides upgrade potential towards 24 % cell efficiency.

Background: A 51-year-old previously healthy woman presented with a perianal mass. The mass has been there for some years and has gradually increased in size ever since with progressive pain when she sits. There was no history of trauma nor injections in this region. Clinically, the mass was not tender and rather soft, with superficially some focal harder spots. A large lipoma was suspected on clinical basis. An ultrasonography and subsequent MRI scan, including sequences following administration of gadolinium contrast medium were performed.

We use the wavelet transform modulus maxima method to investigate the multifractal properties of strand-asymmetry DNA walk profiles in the human genome. This study reveals the bifractal nature of these profiles, which involve two competing scale-invariant (up to repeat-masked distances $\ensuremath{\lesssim}40\phantom{\rule{0.3em}{0ex}}\mathrm{kbp}$) components characterized by H\"older exponents ${h}_{1}=0.78$ and ${h}_{2}=1$, respectively. The former corresponds to the long-range-correlated homogeneous fluctuations previously observed in DNA walks generated with structural codings. The latter is associated with the presence of jumps in the original strand-asymmetry noisy signal $S$. We show that a majority of upward (downward) jumps colocate with gene transcription start (end) sites. Here 7228 human gene transcription start sites from the refGene database are found within $2\phantom{\rule{0.3em}{0ex}}\mathrm{kbp}$ from an upward jump of amplitude $\ensuremath{\Delta}S\ensuremath{\geqslant}0.1$ which suggests that about 36% of annotated human genes present significant transcription-induced strand asymmetry and very likely high expression rate.

Rigorous diffraction theory is a reliable tool to quantify the absorption enhancement in textured thin film solar cells. We provide a line of arguments that make the insights from such an involved analysis accessible to a broader community by using a scalar approach. We show that the scattering response from a textured surface as calculated by a simple scalar model can be related to the measured external quantum efficiency of a solar cell and double-check this model by rigorous calculations. This approach allows estimating the performance of a textured thin film to a certain extent without any sophisticated numerical analysis.

This discussion of endometriosis associated with pregnancy is restricted to external endometriosis. The exclusion of internal endometriosis is based on concurrence in the belief that the two diseases are etiologically separate and their relationship to pregnancy distinctly different. The literature to date suggests that endometriosis associated with pregnancy is infrequent. Articles dealing with the subject specifically are few. The already voluminous and rapidly increasing literature regarding endometriosis deals with etiology, pathogenesis, and management, medical or surgical. Discussions pertinent to endometriosis associated with pregnancy are involved with review of literature with additions of case reports. Scott 1 did service in this respect and subsequently scattered case reports have been recorded. The initial appearance of this subject in a standard textbook was made in 1950. 2 It has been stated that "combining a discussion of endometriosis and pregnancy is in some measure a paradox." This is further supported by the belief that the lesions are associated with infertility, relative and absolute. There are many comments in the abstract bearing upon the effect of the one on the other. These opinions vary in extremes. Goodall, 3 in 1943, stated that in his experience with hundreds of cases of endometriosis he had never seen pregnancy and, further, that it was fortunate the two conditions never coexist. Meigs, 4 originally in 1922, and two years later Sampson, 5 put forth the supposition that the lesion might be favorably influenced by pregnancy. Beecham, 6 in 1949, said, "Nature (since the beginning of time) has employed an efficient prophylactic and curative measure for endometriosis, i.e., pregnancy." In the same discussion he said, "Pregnancy must be considered the ultimate in endocrine therapy, but why the physiologic amenorrhea causes the endometrial implants to regress, we do not know." Randall, 7 in the same year, discussing therapeutic effects of estrogens, said, "Foci of endometriosis seem to improve remarkably during pregnancy." These authors did not offer substantiative evidence for these statements, yet I am sure it must be available. The recommendation to the endometriosis victim to conceive is repeatedly observed in the literature, but whether for its therapeutic effect or in anticipation of associated infertility, is not too clear. This latter concept was productive of cases for this report.

Summary The success of the program depends in turn upon the approach with which it is undertaken. 1. Voluntary. Involvement by the physician concerned produces the greatest educational benefits. 2. Local. The only persons really qualified to evaluate cases of perinatal mortality are those who are entirely familiar with the local conditions. 3. Current. The extreme brevity of most newborn records demands the investigation of the caes of a current basis for accuracy.

This paper reviews recent progress made at CSEM on the development of low-temperature processes for the fabrication of amorphous silicon-based passivated contacts and for the metallization of high-efficiency silicon heterojunction (SHJ) solar cells. Intrinsic a-Si:H passivation layers were optimized by trying to minimize the drop in lifetime usually observed after the deposition of the p-doped a-Si:H layer on top. State-of-the-art passivation levels are obtained, demonstrated by minority carrier lifetimes above 50 ms on lowly doped wafers, and close to 18 ms on actual SHJ cell precursors with buffer layers as thin as 4 nm. Regarding cell metallization, the screen-printing process of low-temperature Ag pastes has been optimized, resulting in finger width as low as 16 µm. Alternatively, a photolithography-free copper electroplating process has been developed. Using inkjet printing of hotmelt for patterning, 25-µm-wide and highly conductive fingers can be deposited. This process was tested in SHJ cell pilot production conditions, showing high cell performance (22.3% median efficiency) and good reproducibility. Finally, using the developed passivated contacts and screen-printing process, SHJ solar cells fabricated with industry-compatible processes showed efficiencies up to 23.1% on large-area devices and up to 23.9% on 4 cm2 devices.

We give an overview on recent progress in the synthesis, fabrication and integration of advanced nanostructured materials for efficient light trapping in high-efficiency thin-film silicon solar cells.

The window-layer stack limits the efficiency of both-side-contacted silicon heterojunction solar cells. We discuss here the combination of several modifications to this stack to improve its optoelectronic performance. These include the introduction of a nanocrystalline silicon-oxide p-type layer in lieu of the amorphous silicon p-type layer, replacing indium tin oxide with a zirconium-doped indium oxide for the front transparent electrode, capping this layer with a silicon-oxide film and applying a postfabrication electrical biasing treatment. The influence of each of these alterations is discussed as well as their interactions. Combining all of them finally enables the fabrication of a highly transparent and electrically well-performing window-layer stack, leading to a screen-printed silicon heterojunction solar cell with 24.1% efficiency. Paths toward industrialization and further improvements are finally discussed.